More efficient cars and trucks, including several hybrid gas-electric vehicles, are on the way.

Conceptually akin to gas-electric hybrid vehicles like the Toyota Prius, the approach uses a hydraulic transmission rather than a mechanical transmission with an internal combustion engine.

Automakers have responded by offering gas-sipping subcompact cars and gas-electric hybrid vehicles.

The postmodern digital age has not caught up to cars, with one notable exception: the hybrid gas-electric vehicle.

Last year, G.M. and Toyota formed a manufacturing partnership to include research and development on fuel cell and gas-electric hybrid vehicles.

Within a year, 10 gas-electric hybrid vehicles will be on the market, and automakers have announced plans for several more.

Evo also has to contend with the rapidly expanding popularity of the hybrid gas-electric vehicles, like the Prius.

It has led some to surmise that this technology when applied to lithium batteries and gas-electric hybrid vehicles will give lead to a bright future for hybrid vehicles.

From a development point of view, the U.S. auto industry estimates that by 2010, there will be over four million gas-electric hybrid vehicles on American roads.

The Consumer Guide to Hybrid Vehicles: Learn about every gas-electric vehicle, and some upcoming models, too.